well i started at 25 psi couldnt get that good of grip so i went to 20 psi and ran some 16.0 (which is bad) and still couldnt grip so well..... i thought about going to 15 cuz some other guys did and it worked well for them but i didnt... i need to drop that puppy a little bit cuz i just couldnt get any bite. i tried launching at 3k rpms 2k, and no reving and still would spin so back to square 1